1. Bring back full-screen incoming call alerts
Prior to Apple's iOS 14 update, the incoming call screen would take over your entire display when your iPhone was unlocked and being used. It was disruptive, sure, but it also got the job done.
Starting with iOS 14, however, Apple changed the incoming call prompt to look more like a typical alert. That is, now it's a small notification that shows up near the top of the screen when you're using your phone. On more than one occasion I've nearly missed a call because I dismissed the alert as yet another annoying notification that didn't immediately need my attention.
To get the more attention-grabbing full-screen alerts back, go to Settings > Phone > Incoming Calls and tap Full Screen.